Development of light-sensitive silver halide emulsions



United States Patent cc U.S. Cl. 96-663 8 Claims ABSTRACT OF THE DISCLOSURE Photographic light-sensitive silver halide materials comprising a polymeric compound containing alkylene (N-alkyl)-amino-alkylene groups linked through hydroxysubstituted oxyalkylene groups and/or such polymeric compounds wherein the hydrogen atoms of said hydroxyl groups are wholly or partly substituted are described.-

This invention relates to a process for producing a photographic silver image by development of exposed light-sensitive silver halide in the presence of compounds influencing the sensitometric characteristics of a lightsensitive silver halide emulsion by an increase of the speed and/or the gradation. The present invention also relates to said compounds used in said process, their preparation and to photographic materials and developing baths containing said compounds.

It is known that the general sensitivity of photographic emulsions, which can already be sensitized optimally throughout the whole range of the spectrum by means of the so-called chemical sensitizers, such as sulphur sensitizers, can be increased if amines or some polyamines such as diethylenetriamine, triethylene tetramine, are added to these photographic emulsions (British patent specification 734,474). Such substances, however, cause an increase of the free silver ion concentration of the emulsion and greatly diminish its stability.

It is also known that an increase of sensitivity can be obtained by incorporating into the photographic material polyethylene glycols, alkylene oxide, polymers obtained by polymerising alkylene oxide in the presence of hexitol ring dehydration products, aliphatic alcohols, aliphatic acids, amines, amides, and phenols (British patent specifications Nos. 548,019, 600,058, 592,676, 748,745, and 748,750).

It is further known that these polyglycols and alkylene oxide polymers should possess a molecular weight of at least 400. In order to obtain a noticeable effect, it is in practice necessary to use compounds having a molecular weight of 1500' to 2000 and more.

Contrary to the other known methods for increasing the sensitivity of silver halide emulsions such as those in which the chemical sensitizers increase the inherent sensitivity and those in which the cyanine dyes increase the spectral absorption, it appears that the final sensitivity of the silver halide emulsion layers in which these compounds are incorporated is higher since these compounds exert a favourable influence on the development of these silver halide layers by means of the usual developers. Consequently these compounds can be considered as development accelerators.-

It is also known, however, that a noticeable increase in sensitivity is only obtained with these compounds when developing in rather slow working developers of the fine grain developer type used in the development of continuous tone images. In fast acting .p-N-methyl-amino- 3,523,797 Patented Aug. 11, 1970 phenol/hydroquinone or l-phenyl 3 pyrazolidinone/ hydroquinone developers, their development accelerating action manifests itself only by a very moderate increase of the speed of the developed photographic material.

'It has been found now that polymeric compounds containing in their polymer chain alkylene-(N-alkyl) aminoalkylene groups and hydroxy-substituted oxyalkylene groups and such polymeric compounds wherein the hydrogen atoms of said hydroxyl groups are partly or wholly substituted, are very suitable for substantially increasing the developability and also the sensitivity of photographic silver halide emulsions on development in slow as well as in fast acting developers.

Polymers, which have proved to be very suitable in that respect, contain recurring units, which can be represented by:

R represents an alkyl group of 1 to 5 carbon atoms, e.g., a methyl, ethyl, propyl, isopropyl, or a substi tuted alkyl group, e.g., a 2-hydroxyethyl group, or an aralkyl group;

R represents a hydrogen atom, an alkyl group, a substituted alkyl group, e.g., a cyanoethyl group,

wherein R represents an alkyl group, an aryl group, or a heterocyclic group including such groups carrying one or more substituents,

Alk and Alk are alkylene groups containing from 2 to 10 carbon atoms or such alkylene groups substituted by, e.g., a hydroxyl group, and groups the carbon chain of which is interrupted by one or more hetero atoms such as oxygen, sulphur, phosphorus, or a substituted nitrogen atom, e.g., an alkyl-substituted nitrogen atom; and

n is a positive integer of at least 3.

The compounds according to the invention can be prepared by reaction of a N-alkyl-dialkanolamine and/or trialkanolamine with a bis-epoxide, more particularly an alkyleneoxy bis-epoxide. The inversed synthetic route viz the reaction of a N-alkyl-containing bis-epoxide with a diol, e.g., an alkylene diol or N-alkyl-dialkanolamine can also be applied.

The reaction is carried out in such a way that the reaction products either in the form of the base or in the salt form are soluble in water.

If the reaction between the diol and the bis-epoxide is too exothermic, care must be taken that the reaction mixture is cooled in order to prevent the formation of gummy products. The optimum reaction temperature is adapted to each polyaddition and usually varies between 50 and C.

When very reactive starting compounds are used, it is sometimes advantageous to mix the reaction products with Water at the stage at which the required degree of addition is attained, so that any further addition, which would lead to the formation of water-insoluble products, is prevented.

In general both starting products are made to react in an equimolar ratio, though an excess of one .of them is not harmful in most cases, except in an addition reaction between very reactive compounds, in which an excess of bis-epoxide should be avoided always in order to prevent the formation of addition products, which either in the form of a base or in the salt form are insoluble in water. Bis-epoxides suitable for use are, e.g., 1,225,6-diepoxyhexane, bis(2,3-epoxypropyl)ether, 1,2-bis(2,3-epoxypropoxy)-ethane, 1,3-bis(2,3-epoxyprpoxy)-propane, 1,4- bis(2,3 epoxypropoxy)-butane, 1,3 bis(2,3 epoxypropoxy) 2 propanol, 1,3-bis(2,3 epoxypropoxy)-butane, 2,3 2,3 "-diepoxy-N-alkyl-dipropylamine, 5,6-epoxy-hexane carboxylic acid-2,3-epoxypropyl ester, bis(2,3-epoxypropyl) -sulphone.

Tri-epoxides such as tri(2,3-epoxypropoxy)-phosphate and 2,4,6-tri(2,3-epoxypropoxy)-s-triazine can also be used.

Particularly suitable N-alkyl-dialkanolamines are N- alkyl diethanolamines such as N-methyl-, N-ethyl-, N- propyl-, N-isopropyl-, and N-butyl-diethanolamines, N- alkyl-dipropanolamines such as N-methyl-di-isopropanolamine, triethanolamine, tri isopropanolamine, N amethylbenzyl-diethanolamine, etc.

As an illustration of the preparation of said addition products a general procedure of preparation is given hereinafter.

1 mole of a N-alkyl-dialkanolamine is preheated at a temperature comprised between and 160 C. (see Table l), and subsequently 1 mole of a bis-epoxide is added thereto portion-wise whilst stirring. The addition of the bis-epoxide is regulated so that no gummy products are formed. If necessary the mixture is cooled during the addition. After the addition of the bis-epoxide, the reaction mixture is allowed to react further (see Table l) in order to obtain products with a higher molecular Weight. Care should be taken, however, that the reaction is stopped when formation of water-insoluble gummy products begins. With very reactive starting products it is sometimes necessary to add Water to the reaction mixture after the addition of the bi-epoxide to avoid gum formation.

In Table 1 hereinafter a survey of suitable starting products and reaction conditions is given.

TABLE I 00111- Reac- Reaction pound tion temp.

0. Used alkanolamine or diol Used epoxide time 0.) Remarks 1 CHzCHzOH O 1 h 100 Water-soluble viscous mass. H CN CI'I9,CIICI'I2O (OH2)2O CHzCE-CHZ CH2CH2O H 2 CHzCHzOH /O\ 31130- 100 Do.

HaC-N CH2CHCH2O(CH2)4OCH2CHCH2 CHzCHzOI-I 3 CHzCHzOH O OH O 8 h 25 Dissolves in water in l acetate fonn. HaO-N CH2'-CHCH2O OH2CHCH2OCH2 H-CH2 CH CHzOH 4 .i CH2OH2OH 1 h -80 After condensation add water to obtain H3C-CH2-N CHz-C HCHzO (CH2) 2O CI-IzCH-CH2 a 10% solution.

CHzCHzOH 5 CHzCHzOH /O\ /O\ 2 h 30'- 60 Do.

H;CCH2N CH2CHCH2O (CH2)40 CHzCH--CH2 CHzCHzOH (i CHzCHzOH O OH 0 21130.. 60 Do.

I H CCHz-N CH CHCHQOCHzCHCHzOCHzCH-CH2 CHzOHZOH 7 CHaOHzOH 0 2h 30- 60 Do.

H O (CHmN CH CHCHZO(CH2) OCH CHCHZ CHzCHzOH 8 CHzOHzOH O 3 h 30'- 60 Do.

H3C(CH2)2N CH -CHCHZO (CHmO OHzCH CH CHzCHzOH 9 OHzOHzOH OH 2h30'-- 60 Do.

I H3C(CH2)2N CHz-CHCH2OCH2CHCH2OCHzCH-CH2 OHZCHZOH 10 GHQCHQOH 1 11 30. 150-160 Water-soluble viscous mass. NGH;CHOH CH2CHCH2O (CHmO CH CH-CH2 CH2OH2OH 11 CH2CH2OH 0 2 h -160 Do.

NCH2CH2OH CH;OHCH O(OH2)4OCHzOH-CHz CHzOH OH 12 (111 0132011 1 h 30- -30 Water-soluble viscous A mass. H ON H C\ GHzOH-()Hz 01120312011 CH-N Oom- Reac- Reaction pound tion temp. N 0. Used alkanolamine or diol Used epoxide time 0.) Remarks 13 OH 13 h 30". 150-170 Do.

H30(EHOHZ OH OH CHCHZO(CH2)4OCH2CHCH N-OH: HCH

H C-(EHO H2 14 CH OH CH OH 18 h.. 150-170 Dissotlvtesfin water in ace a e orm. H-N CHz-OHCHzO (GH2)40CH2CHCH2 CHzCHzO H 15 HO CH CHzOH 3 h 110-125 Dissolves in water in tolusulphenate form. H O CHzCH-CH2 C H-N HQC CHzCH-CHz 16 H O CHzCHzOH O h 100-130 Water-soluble viscous mass. CH-N CHz-CHCH2O (CH2)40 CHzCHCH2 3O CH2CH2OH 17 011 0112011 /0\ 2 h 100 Aftceilcondensation a we or to obtain H C(CH2) N CH2CHCHzO (C'Hz) 0 CH2OH-CH2 a 10% solution.

CHzCHzOH 18 HO OH OH CH2OH2OH O 1 h 30- 100 Water-soluble viscous mass. NCHZCH2N CH OHCH 0(CH) OCH CH-CH HO CHzCHz CHzCHzOH 19 CHzCHzOHzOH H C\ CH 1 h 30- 125 Do.

i I CHaCHqCHzOH CH2-CH-CH2-NCH2CHCHz 20 Same as above 0 1 h 100 After condensation add water to obtain CHz-CHCH2O (CH2) 2OCH-OH a 10% solution.

21 CHzCHa H O CH3 3 h 125 Water-soluble viscous mass. HO CH2CH2-N CHzCHzOH O\ OH CHzCHz CH2CHCH2NCH2-CHCH2 By the complete or partial substitution of the hydrogen atoms in the free hydroxyl groups of the epoxide addition products very valuable development accelerating agents are obtained as well. Suitable reactants for this substitution reaction are carboxylic acid chlorides or anhydrides (e.g., acetyl chloride, acetic anhydride, maleic anhydride), sulphonyl chloride, isocyanates, and unsaturated aliphatic compounds such as vinyl compounds, e.g., acrylonitrile and methacrylonitrile. The following preparation examples illustrate the above mentioned substitution reaction.

COMPOUND 22 To a solution of 29 g. (0.1 mole) of compound 12 of Table I in 100 ccs. of dioxan a solution of 19.6 g. (0.2 mole) of maleic anhydride in 75 ccs. dioxan is added dropwise at reflux temperature in 30 min. An oily precipitate is formed. Refluxing is continued for 3 hours whilst stirring. Subsequently the dioxan is decanted from the viscous oil. The latter is extracted repeatedly with warm dioxan and finally thoroughly washed and kneaded with ether. The residue is then dried under reduced pressure at 60 C. The resulting fatty product is soluble in water. Yield: 46.5 g.

COMPOUND 23 To a suspension of 32 g. (0.1 mole) of compound 2 of Table I in 100 ccs. of dioxan a solution of 22.8 g. (0.2 mole) of methylsulphochloride in ccs. of dioxan is added dropwise at reflux temperature in 30 min. Refluxing is continued for 2 /2 hr. whilst stirring. The suspension is then concentrated by evaporation. The resulting residue is added to 30 ccs. of methanol and precipitated with ether. The residue is Washed repeatedly with ether and dried in vacuo at 60 C. The resulting product is soluble in Water. Yield: 44 g.

COMPOUND 24 To a suspension of 32 g. (0.1 mole) of compound 2 in ccs. of dioxan a solution of 14.2 g. (0.2 mole) of ethyl isocyanate in 50 ccs. of dioxan is added dropwise at 50 to 60 C. in 5 min. The resulting solution is further heated at the same temperature for 2 /2 hr. whilst stirring. Subsequently the total bulk is concentrated by evaporation. The resulting oil is added to 75 ccs. of methanol and precipitated with ether. The residue is repeatedly washed with ether and dried in vacuo at 60 C. The product is soluble in water. Yield: 35 g.

COMPOUND 25 To a suspension of 32 g. (0.1 mole) of compound 2 in 100 ccs. of dioxan a solution of 19.6 g. (0.2 mole) of maleic anhydride in 50 ccs. of dioxan is added dropwise at reflux temperature in 15 min. Refluxing of the suspension is continued for 2 /2 hr. whilst stirring. Afterwards the dioxan is decanted from the viscous oil and the latter is kneaded with ether. The residue is then dried in vacuo at 60 C. The product is soluble in water. Yield: 50 g.

7 COMPOUND 26 To a suspension of 32 g. (0.1 mole) of compound 2 in 150 ccs. of dioxan a solution of 10.6 g. (0.2 mole) of acrylonitrile in 50 ccs. of dioxan is added dropwise at reflux temperature in 30 min. Refluxing is continued for 2 /2 hr. whilst stirring. Subsequently, the total bulk is concentrated by evaporation. The resulting oil is added to 300 ccs. of methanol and precipitated with ether. The residue is repeatedly washed with ether and dried in vacuo at 60 C. The product is soluble in water. Yield: 32 g.

COMPOUND 27 v To a suspension of 32 g. (0.1 mole) of compound 2 in 200 ccs. of dioxan 20.4 g. (0.2 mole) of acetic anhydride are added dropwise at reflux temperature in min. Refluxing is continued for 1 hr. Subsequently the total bulk is concentrated by evaporation. The resulting oil is added to a minimum amount of methanol and precipitated with ether. The residue is repeatedly Washed with ether and dried in vacuo at 60 C. The product is soluble in water. Yield: 39 g.

COMPOUND 28 To a suspension of 32 g. (0.1 mole) of compound 2 in 100 ccs. of dioxan a solution of 36.8 g. (0.2 mole) of o-sulphobenzoic anhydride in 100 ccs. of dioxan is added dropwise at reflux temperature in min. Refiuxing of the suspension is continued for 3 hr. whilst stirring. Subsequently the dioxan is decanted from the viscous oil. The oil is then repeatedly extracted with warm dioxan, thoroughly washed and kneaded with ether. Finally, the residue is dried in vacuo at 60 C. The product is soluble in water. Yield: 59 g.

COMPOUND 29 To a suspension of 32 g. (0.2 mole) of compound 2 in 100 ccs. of dioxan a solution of 29.6 g. (0.2 mole) of phthalic anhydride in 150 ccs. of dioxan is added drop- Wise at reflux temperature in min. Refluxing of the suspension is continued for 4 hr. whilst stirring. Subsequently the dioxan is decanted from the viscous oil. The latter is extracted repeatedly with warm dioxan and thoroughly washed with ether. The residue is dried in vacuo at 60 C. The product is soluble in diluted sodium hydroxide. Yield: 55 g.

The development accelerators used according to the present invention can be added as a base or in the salt form to the coating composition of a silver halide emulsion and/or incorporated into a water-permeable layer, which applied under or on top of the emulsion layer forms a water-permeable system with the silver halide emulsion layer and thus can come into effective contact with the silver halide.

The development accelerators can be incorporated into the coated emulsion layer either by treating the emulsion layer with an aqueous solution of these development accelerators or by coating this layer with a water-permeable layer containing the development accelerators, or also by bringing the development accelerators from a water-permeable layer lying under the emulsion layer and comprising said development accelerators, by diffusion into effective contact with the silver halide.

The water-soluble development accelerators can be added to the light-sensitive silver halide emulsion during different preparation steps of the light-sensitive material:

, for instance they can be incorporated therein as a separate addition either mixed with one or more ingredients, which are used in the preparation of the silver halide grains during the physical or chemical ripening process, or another moment preceding the coating of the emulsion.

The development accelerators are preferably added to the silver halide emulsion composition after the chemical ripening process and just before coating the emulsion.

The development accelerators are preferably added in dissolved form in water or in aqueous mixture of water and water-miscible organic solvents that do not impair the photographic properties of the light-sensitive silver halide emulsion. When the polyaddition products are not sul'ficiently soluble in water in their base form, they are converted into their salt form by neutralization, e.g., with an acid such as sulphuric acid, hydrochloric acid, p-toluenesulphonic acid, or acetic acid.

The optimum amount of development accelerator added to the silver halide emulsion depends on the very compound, on the nature of the colloid binding agent for the silver halide grains, and on the amount and the kind of the silver halide in the emulsion. In general, however, the development accelerators are added to the light-sensitive material in amounts ranging from mg. to 10 g. per mole of silver halide. In the developing bath they are normally used in amounts ranging from 0.1 g. to 10 g. per liter. If necessary, these compounds can also be added in amounts exceeding these limits.

The steps of increasing the sensitivity according to the present invention can be combined with a method known as chemical sensitization, in which together with the above-mentioned development accelerators usual amounts of chemical sensitizers are added to the silver halide emulsion, e.g., sulphur-containing compounds such as allyl isothiocyanate, allylthiourea or sodium thiosulphate, reducing compounds such as the tin compounds described in the Belgian patent specifications 493,464, filed Jan. 24, 1950, and 568,687 filed June 18, 1958, both by Gevaert Photo-Producten N.V., the iminoaminomethane sulphinic acid compounds described in the British patent specification 789,823, filed Apr. 29, 1955, by Gevaert Photo-Producten N.V., or noble metal compounds such as gold, platinum, palladium, iridium, ruthenium, and rhodium compounds. As a matter of fact, the sensitizing action of the development accelerators used in the present invention comes in addition to the sensitizing action of the sensitizing compounds originally present in gelatin.

The development accelerators applied in the present invention can also be used in combination with stabilizers and fog-inhibiting compounds for the silver halide emulsion, for instance with mercury compounds or organic sulphur-containing compounds that form an insoluble silver salt with silver ions, preferably heterocyclic nitrogen-containing thioxo compounds such as benzothiazolin- 2-thione and l-phenyltetrazolin-S-thione, the compounds described in the Belgian patent specifications 571,916 and 571,917 both filed Oct. 10, 1958, by Gevaert Photo-Producten N.V., and compounds of the oxytriazolopyrimidine type, e.g., 5-methyl-7-hydroxy-s-triazolo 1,5-a] pyrimidine. The combination with sensitizing and stabilizing cadmium salts in the light-sensitive material as well as in the developing bath can also be applied.

Other compounds, which sensitize the photographic emulsion by development acceleration, such as organic onium compounds and polyonium compounds, preferably of the ammonium or sulphonium type, e.g., quaternary tetraalkylammonium salts, alkylpyridinium salts, bis-alkylene-pyridinium salts, alkylquinoline salts, and trialkylsulphonium salts can be used together with the development-accelerators according to the invention in the developing solution as well as in the light-sensitive material. Other ingredients, such as colour couplers, developing substances, hardening agents, and wetting agents, can also be added to the emulsions in the ordinary way.

The development of low-sensitive as well as of highsensitive, of fine-grain as well as of coarse-grain silver halide emulsions is accelerated by the action of the abovementioned development accelerators. These products can be applied for accelerating the development of X-ray emulsions as well as of the most dilferent spectrally or nonspectrally sensitized emulsions. They can be incorporated into the photographic emulsion either with or without optical sensitizers and can be used for increasing the sensitivity of negative emulsions as well as of positive emulsions.

The following examples illustrate the invention.

EXAMPLE 1 A Washed negative gelatin silver iodobromide emulsion (average grain size of the silver halide: 0.8 the silver halide of which consists of 94.5 mole percent of silver bromide and 5.5 mole percent of silver iodide, is ripened at 45 C. The emulsion ready for coating contains per kg. 50 g. of silver halide, 75 g. of gelatin, 30 mg. of optical sensitizer according to the following structural formula:

50 mg. of 5-methyl-7-hydroxy-s-triazolo[1,5-a]pyrimidine as a stabilizer, and 500 mg. of saponine as a wetting agent.

This emulsion is divided into several aliquot portions and to the separate portions is added one of the development accelerators according to the present invention. The emulsion portions are separately applied to a cellulose triacetate support and dried.

The test strips obtained are then exposed in the same conditions through a grey Wedge and developed for 7 minutes at C. in a fine-grain developer of the following composition:

Water-800 ccs. N-methyl-p-N-hydroxypheny1-ammonium sulphate-Z g. Hydroquinone-S g.

Anhydrous sodium sulphite-IOO g.

Boric acid5 g.

Potassium bromide-0.5 g.

Water to 1000 ccs.

The speed is given in relative exposure values in respect of an emulsion to which no sensitizer Was added. A decrease of the exposure value of means a doubling of the speed.

Amount of compound per Sensitometrlc results Number of the kg. of emuladded compound sion Fog Gamma Speed EXAMPLE 2 An emulsion as described in Example 1 is used, except that the test strips after having been exposed, are developed for 5 min. at 20 C. in a classical fast acting hydroquinone/p-N-methylaminophenol developer of the following composition:

Water800 ccs. N-methyl-p-N-hydroxyphenyl-ammonium sulphate2 g. Hydroquinone-S g.

Anhydrous sodium sulphite-ZS g.

Crystalline sodium carbonateg.

Potassium brom1de1 g. 1 Water to 1000 ccs.

Amount of compound Sensitometrle results added per kg. Added compound emulsion Fog Gamma Speed 0. 08 0. 73 79 Polyethylene glycol mg 0.13 0. 81 78 012E220 (CH2OHzO)zoH 300 mg 0. 10 0.86 75 2 100mg 0.12 0.63 70 0. 86 68 0.86 65 0.60 64 0. 73 68 EXAMPLE 3 An emulsion as described in Example 1 is used. The test strips obtained are exposed in the same conditions through a grey wedge and developed for 11 minutes in a fine-grain developer of the following composition:

N-methyl-p-N-hydroxyphenyl-ammonium sulphate-4.5 g. Anhydrous sodium sulphite90 g.

Sodium chloride-30 g.

Boric acid till pH 7.8.

Water to 1000 ccs.

Amount of compound per Sensltometrlc results Number of the kg. of emuladded compound sion Fog Gamma Speed 0. 07 0. 42 189 0. 10 0. 50 174 0. 09 0. 56 0. 13 0. 60 164 0. 13 0. 60 166 0. 20 0. 63 158 0. 10 0. 50 174 0. 09 0. 56 165 0. 19 0. 54 157 0.20 0. 68 149 0. 15 0. 60 163 g 0. 16 0. 61 161 0. 08 0. 62 165 19 300 mg 0. 08 0. 58 168 1 g 0.12 0. 63 162 What we claim is:

1. Process for developing photographic materials containing light-sensitive silver halide, wherein the development is carried out in the presence of a polymeric compound containing alkylene(N alkyl) amino alkylene groups linked through hydroxy-substituted oxyalkylene groups and/or such polymeric compounds wherein the hydrogen atoms of said hydroxyl groups are wholly or partly substituted.

2. Process for developing photographic materials containing light-sensitive silver halide according to claim 1, wherein the development is carried out in the presence of a water-soluble polymeric compound obtained in basic form by polyaddition of a N alkyl dialkanolamine and/ or a trialkanolamine with a bis-epoxide or by polycondensation of a N-alkyl-containing bis-epoxide with a diol.

3. Process for developing photographic materials containing light-sensitive silver halide, wherein the development is carried out in the presence of a polyaddition product containing the following structural units or these units in salt form:

Alk and Alk each is an alkylene group containing from 2 to 10 carbon atoms, or such a group wherein the carbon chain is interrupted by one or more hetero atoms,

R is an alkyl group of 1 to 5 carbon atoms, or an aralkyl group,

R is a hydrogen atom, an alkyl group, a --COR group, a CO-NH--R group, or a -SO R group,

1 1 wherein R is an alkyl group, an aryl group, or a heterocyclic group, and n is an integer of at least 3.

4. A photographic light-sensitive silver halide material comprising a polymeric compound containing alkylene (N alkyl) amino alkylene groups linked through hydroxy-substituted oxyalkylene groups and/or such polymeric compounds wherein the hydrogen atoms of said hydroxyl groups are wholly or partly substituted.

5. A photographic light-sensitive silver halide material comprising a polyaddition product containing the following structural units or these units in salt form:

wherein:

6. A photographic light-sensitive silver halide material according to claim 4 and containing said polymeric compound in-an amount ranging from 100 mg. to 10 g. per mole of silver halide.

7. A photographic developing bath for exposed lightsensitive silver halide materials containing from 0.1 g. to 10 g. per liter of a polymeric compound obtained in basic form by polyaddition of a N-alkyl-dialkanolamine and/ or a trialkanolamine with a bis-epoxide or by polyaddition of a N-alkyl-containing bis-epoxide with a diol.

8. A polymeric compound containing alkylene (N- alkyl)amino-alkylene groups or these groups in salt form, wherein this polymeric compound has been prepared in its basic form according to one of the following methods:

(a) polyaddition of a N-alkyl-dialkanolamine with a bis-epoxide or tris-epoxide, or

(b) polyaddition of a N-alkyl-containing bis-epoxide with a diol.

References Cited UNITED STATES PATENTS 3,307,948 3/1967 Thiers et a1 96-663 NORMAN G. TORCHIN, Primary Examiner 5 A. T. SURO PICO, Assistant Examiner U.S. Cl. X.R. 

